Expansion joints for roofs

ABSTRACT

A roof joint construction is provided which includes an insertable precompressed expansible elongated filler or core element of open cell polyurethane or the like, with an impregnant, for insertion at joints in a roof deck for engagement with the roof, the insulation on the roof and the roof deck. The filler or core is preferably held, prior to use, in a compressed condition in any desired manner, such as by a cartridge, cartridge and cap or by a vacuum packing, with interposed release sheets, if desired. Upon removal for installation the filler or core element is inserted to the desired depth at the space at the joint, and restrained against further downward movement while the expansion in the space and above the space takes place. The top of the strip may have an elastic and flexible cover thereon to protect the filler or core. Before or after the removal of the cap, if a cap is employed, the roofing covering is applied. A final roofing covering may be used over the joint, if desired.

United States Patent 1 1 Mullen 154] EXPANSION JOINTS FOR ROOFS WilliamT. Mullen, 65 West Street Road, Wyncote, Pa. 18974 221 Filed: May7, 1971211 Appl.No.: 141,271

[76] lnventor:

Related U.S. Application Data [63] Continuationin-part of Ser. No.848,251, Aug. 7,

1969, abandoned.

Primary Examiner-John E. Murtagh Attorney-Zachary T. Wobensmith [57]ABSTRACT A roof joint construction is provided which includes aninsertable precompressed expansible elongated filler or core element ofopen cell polyurethane or the like, with an impregnant, for insertion atjoints in a roof deck for engagement with the roof, the insulation onthe roof and the roof deck. The filler or core is preferably held, priorto use, in a compressed condition in any desired manner, such as by acartridge, cartridge and cap or by a vacuum packing, with interposedrelease sheets, if desired. Upon removal for installation the filler orcore element is inserted to the desired depth at the space at the joint,and restrained against further downward movement while the expan- 3Claims, 7 Drawing Figures PATENTDJAH30 I973 13. 7 l 3, 263

SHEET 1 OF 2 FIG.

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32 FIG. 7

nvvewron I WILL/AM r. MULLEN @TQW ATTORNEY EXPANSION JOINTS FOR ROOFSREFERENCES TO RELATED APPLICATION This application is a continuation inpart of my prior U.S. application for Expansion Joint for Roof, filedAug. 7, 1969, Ser. No. 848,251, now abandoned.

BACKGROUND OF THE INVENTION 1. Field of the Invention This inventionrelates to expansion joints for roofs and more particularly to animproved insertable expansible filler or core element for use inroofjoints and the joint construction. 2. Description of the Prior ArtLarge roof areas must have provisions to accomodate expansion.

Many different methods and materials have heretofore been proposed andthese usually rely on some waterproof but elastic material that willstretch to handle the expansion of the joint and then contract when thejoint contracts. Many of the materials proposed are adversely affectedby strong sunlight and other exposed weathering conditions including theaction of ozone and air so that the materials lose elasticity andotherwise age and deteriorate. The most acceptable systems employ a curbbuilt up above the insulation but these systems are expensive andinvolve many steps or operations for completion.

One expansion joint of the character referred to above is shown in U.S.Pat. No. 3,093,934 to Underhill, which includes angles and fillet stripswith an inverted U-shaped flexible insert and a cover strip of flexibleplastic and covering tapes.

Numerous expansion joints similar to the Underhill joint are alsoavailable and many other expansion joints have been proposed.

The patent to Thompson, U.S. Pat. No. 1,885,391, shows an expansionjoint for concrete pavements in which, in one form a plasticnoncompressible filler material, preferably bituminous, fills the lowerportion of the space between the slabs and the upper portion of thespace is closed but only partially filled by a strip of compressiblevulcanized sponge rubber which is flush with the upper faces of theslabs.

In another form of the Thompson disclosure the sponge rubber strip isvulcanized to a pair of sheet metal strips with stamped out anchoragemembers to be embedded in the concrete slab. Paper strips to prevententry of wet concrete below the rubber strip are provided and wires maybe employed to hold the sponge rubber in compressed condition until theconcrete has set when the wires may be cut and withdrawn. Thompson doesnot have a joint for roofs and cannot obtain any comparable ease of use,multiple seal and protection of the sealing strip as attained byapplicant.

Fischer, in U.S. Pat. No. 2,431,385, shows an expansion joint forconcrete pavements with the use of a sponge rubber strip with a seepageproofing elastic surface filler around the body but with the fillerdisposed wholly below the upper and outer surfaces of the pavements. Noprovision is made in Fischer for a projecting sealing element expandedat its exposed portion to a greater extent than the remaining portion sothat the only sealing by the sponge rubber is within the space betweenthe ends of the concrete slabs.

Cooper, in U.S. Pat. No. 3,255,680, shows ajoint for cement pavementswhich comprises an elongated metal strip with flanges for retention inthe concrete'and an elongate block secured to the top of the strip whichblock is of compressible but slow recovery material such as apolyurethane foam. The top of the block in the finished construction isflush with the top of the pavement.

Rhodes, in U.S. Pat. No. 3,276,334, shows a joint filler strip ofexpansible material which also has no provision for expansion externallyof the slab and thus has only a limited character of seal.

My prior U.S. Pat. No. 3,446,340, shows the use of a central highlycompressed sealing strip with a finished C-shaped cover or binder stripthereon which are wholly within the space between the panels. The stripand cover do not project therebeyond and if they did could still notexpand to provide additional sealing outside the space.

SUMMARY OF THE INVENTION In accordance with the invention an expansionjoint is provided which includes an insertable elongated precompressedand reexpansible filler or core element for insertion at joints in aroof deck to a predetermined depth, the lower part and inserted partexpanding to fill the space between deck sections and the top part uponrelease expanding to a greater extent for further sealing with theexposed upper edge protected against sun light, ozone and air.

It is accordingly the principal object of the invention to provide anexpansion joint for roofs which includes a precompressed andreexpansible insertable element which can expand to fill the space atthe joint and thereabove for engagement with applied roofing.

It is further object of the invention to provide a precompressedexpansible sealing element which can be readily transported to the placeof use, which will be relatively inexpensive, and which will be easy touse.

It is a further object of the invention to provide a sealing element ofthe character aforesaid which will provide an effective seal and whichwill facilitate the construction of an expansion joint for roofs and thelike.

It is a further object of the invention to provide an improved expansionjoint for roofs in which an expansible filler or core element isemployed which simultaneously presses against the roofing, theinsulation and the roof deck in sealing relation.

Other objects and advantageous features of the invention will beapparent from the description and claims.

BRIEF DESCRIPTION OF THE DRAWING The nature and characteristic featuresof the invention will be more readily understood from the followingdescription taken in connection with the accompanying drawings formingpart thereof, in which:

FIG. 1 is a fragmentary perspective view of a portion of one form ofsealing element in accordance with the invention prior to use;

FIG. 2 is a fragmentary perspective view of another form of sealingelement in accordance with the invention prior to use;

FIG. 3 is a vertical sectional view showing an intermediate stage ofinstallation of the sealing element of FIG. 1;

FIG. 4 is a vertical sectional view showing a later stage than FIG. 3 inthe installation of the sealing element of FIG. 1;

FIG. 5 is a vertical sectional view showing an intermediate stage ofinstallation of the sealing element of FIG. 2;

FIG. 6 is a vertical sectional view showing a later stage ofinstallation of the sealing element of FIG 2; and

FIG. 7 is a vertical sectional view showing a completed expansion jointemploying the element of FIG. 2.

It should, of course, be understood that the description and drawingsherein are illustrative merely, and that various modifications andchanges can be made in the structure disclosed without departing fromthe spirit of the invention.

Like numerals refer to like parts throughout the several views.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now more particularlyto the drawings and particularly FIG. 1 thereof, a portion ofa fillerelement employed in connection with the invention is shown at 10 andincludes an interior soft highly compressed sealing strip 11. The strip11 is preferably composed of an open cell polyurethane plastic orsimilar cellular material which in fully expanded condition ispreferably impregnated with a waterproofing and water repellant materialwhich may also be adhesive. Asphalt, butyl and waxes are suitableimpregnants. The extent of compression after impregnation will bedetermined by the nature of the seal which is desired upon subsequentreexpansion, but is such that the joint is at all times sealed by thestrip 11 against the passage of water and is capable of responding tochanges in the width of the space in which it is used upon eitherexpansion or contraction of the roof deck. A compression of the order oftwo and one half to one and up to five to one can be employed, dependingupon the conditions of use.

The sealing strip 11 is shown as rectangular in cross section, and,along one edge, which is the exposed, edge and a short distance downeach side, is provided with a flexible and transversely extensiblecovering 12, which may be a polyurethane or acrylic coating, to protectthe impregnant and the strip 11 from the action of ozone, oxidation bythe air, and ultra-violet rays from the rays of the sun.

The sealing strip 11 shown in FIG. 1, is preferably retained incompressed condition prior to use by an elongated inverted U-shapedholding or retainer channel 20, with an interposed release sheet 21 toprevent adherence of the strip 11 to the retainer channel 20. Theholding or retainer channel 20 can be made of metal or of syntheticplastic but must have adequate strength to effect its holding action forthe sealing strip 11 in compressed condition until release thereof isdesired.

The retainer or holding channel 20 preferably has a top section 22 andside legs 23 extending therefrom, preferably of greater depth than thatof the strip 1 l.

The mode of use of the filler strip 10 illustrated in FIG. 1 will now bepointed out.

In FIGS. 3 and 4, a roof deck of relatively rigid roof panels 30, whichmay be of concrete or any other desired material, having insulatingpanels 31 superposed thereon is shown, with a space 32 therebetween atwhich an expansion joint is desired. The roof panels 30 have spacedfaces 33 and the insulating panels 31 have spaced faces 34.

A filler element 10 shown in FIG. 1, in compressed and unexpandedcondition, is prepared for insertion by partial removal of the holdingor retainer channel 20 which permits initiation of expansion of thepreviously confined portion of the strip 11 into sealing engagement withthe roof panels 30 and insulating panels 31.

Before expansion occurs the filler element 10 is inserted in the space32 to the desired depth and limit pins 35 inserted therein atthe desireddepth locations. As expansion occurs the strip 11 expands outwardlyuntil it engages the faces 33 and the faces 34.

A plurality of layers 36 of roofing felt with asphalt or pitch, or thelike, can be applied over the panels 31, as illustrated in FIG. 3, withasphalt application if desired in the manner well known for built uproofing.

The holding or retainer channel 20 is then completely removed and theremoval of the channel 20 will permit the expansion of the unrestrainedportion of the strip 11 above the space 32 to expand into sealingengagement with the roofing layers 36 at their edges and flare outwardlythereabove as shown in FIG. 4. The upper edge covering 12 does notprevent this flaring nor the sealing engagement of the portion of thestrip 11 therebelow.

Upon change of dimension of the space 32 by expansion and contractionthe strip 1 1 in the space 32 will expand and contract withoutdisruption of the sealing with the roofing, the insulation or the roofdeck.

Referring now more particularly to FIG. 2 of the drawings, a portion ofanother filler element in accordance with the invention is there shownat 10a and includes a compressible and reexpansible sealing strip 11 aspreviously described. 7

The filler element 10a preferably has a covering 12 and is retained incompressed condition by a lower elongated U-shaped retainer channel 24having a bottom wall 25 and side legs 26. A lower release sheet 21a isinterposed between the strip 11 and the channel 24 to facilitate removalof the channel 24 when desired.

An upper cap 24a having a top'wall 22a and side legs 23a contains theupper portion of the strip 11 in compressed condition until it isremoved. An upper release sheet 21b is interposed between the strip 11and the cap 24a to facilitate removal of the cap 24a when desired.

The mode of use of the filler strip 10a illustrated in FIG. 2 will nowbe pointed out. i

In FIGS. '5, 6 and 7 roof panels 30 and insulating panels 31 are shownas before.

The filler element 10a as shown in FIG. 2 in precompressed andunexpanded condition is prepared for insertion by removal of theretainer channel 24 and, before expansion occurs, is inserted into thespace 32 to the desired depth as determined by limit pins 35 insertedtherein. The expansion of the portion of the strip 11 in the space 32occurs until it engages the faces 33 and the faces 34 as illustrated inFIG. 5.

A plurality of layers 36 of roofing felt with asphalt or pitch areapplied as illustrated in FIG. 6 and the cap 24a removed to permit thestrip 11 to expand into sealing engagement with the roofing layers 36.

The remaining portions of the strip 11 above the roofing paper 36 willexpand into a flared shape as before.

If desired, an additional cap layer of roofing felt 37 with asphalt orpitch can then be applied, to cover the exposed and coated upper edge ofthe strip 1 1.

Upon change of dimension of the space 32 by expansion and contractionthe strip 1 l in the space 32 will expand and contract withoutdisruption of the sealing with the roofing, the insulation and the roofdeck.

1 claim:

1. An expansion joint for roofs and the like comprising roof panels withspaces therebetween,

insulation panels superposed on said roof panels with spacestherebetween corresponding to the spaces between the roof panels,

an elongate filler strip of precompressed and reexpansible cellularmaterial with an adhesive impregnant inserted in said spaces and insealing engagement with said roof panels and with said insulation panelsand extending above said insulation panels,

said insulation panel having built up roofing superposed thereon withwhich said strip is in sealing engagement,

said strip above said roofing being flared outwardly.

2. The combination defined in claim 1 in which said strip has members inengagement therewith for limiting the depth of insertion of said stripin said spaces.

3. The combination defined in claim 1 in which said strip along anexposed edge having a flexible and elastic protective covering.

1. An expansion joint for roofs and the like comprising roof panels withspaces therebetween, insulation panels superposed on said roof panelswith spaces therebetween corresponding to the spaces between the roofpanels, an elongate filler strip of precompressed and reexpansiblecellular material with an adhesive impregnant inserted in said spacesand in sealing engagement with said roof panels and with said insulationpanels and extending above said insulation panels, said insulation panelhaving built up roofing superposed thereon with which said strip is insealing engagement, said strip above said roofing being flaredoutwardly.
 1. An expansion joint for roofs and the like comprising roofpanels with spaces therebetween, insulation panels superposed on saidroof panels with spaces therebetween corresponding to the spaces betweenthe roof panels, an elongate filler strip of precompressed andreexpansible cellular material with an adhesive impregnant inserted insaid spaces and in sealing engagement with said roof panels and withsaid insulation panels and extending above said insulation panels, saidinsulation panel having built up roofing superposed thereon with whichsaid strip is in sealing engagement, said strip above said roofing beingflared outwardly.
 2. The combination defined in claim 1 in which saidstrip has members in engagement therewith for limiting the depth ofinsertion of said strip in said spaces.